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INFO: rcu detected stall in try_check_zero

Status: auto-obsoleted due to no activity on 2025/02/23 21:01
Reported-by: syzbot+3d029d9ca10e3755b826@syzkaller.appspotmail.com
First crash: 458d, last: 458d
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in try_check_zero kernel 1 66 2110d 2552d 0/29 auto-closed as invalid on 2020/09/05 16:29
upstream INFO: rcu detected stall in try_check_zero (5) kernel 1 syz error error 2 34d 410d 0/29 upstream: reported syz repro on 2025/01/02 10:34
linux-6.1 INFO: rcu detected stall in try_check_zero (2) 1 C 1 8h56m 8h56m 0/3 upstream: reported C repro on 2026/02/16 13:40
upstream INFO: rcu detected stall in try_check_zero (2) kernel 1 1 1979d 1979d 0/29 auto-closed as invalid on 2020/12/15 14:13
upstream INFO: rcu detected stall in try_check_zero (3) kernel 1 2 1495d 1498d 0/29 closed as invalid on 2022/02/08 10:10
upstream INFO: rcu detected stall in try_check_zero (4) kernel 1 2 988d 1054d 0/29 auto-obsoleted due to no activity on 2023/09/02 21:24

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (2 ticks this GP) idle=a13c/1/0x4000000000000000 softirq=13193/13195 fqs=0
	(detected by 1, t=10505 jiffies, g=15097, q=126 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4304 Comm: kworker/0:8 Not tainted 6.1.117-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: rcu_gp process_srcu
RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:228 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:240 [inline]
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:444 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:1030 [inline]
RIP: 0010:trace_hrtimer_cancel include/trace/events/timer.h:297 [inline]
RIP: 0010:debug_deactivate+0x8c/0x280 kernel/time/hrtimer.c:483
Code: e8 49 a0 10 00 89 dd 48 89 e8 48 c1 e8 06 48 8d 3c c5 e8 08 9a 8e be 08 00 00 00 e8 2e 2a 68 00 31 db 48 0f a3 2d 1c 1d 20 0d <40> 0f 92 c5 0f 92 c3 bf 02 00 00 00 89 de e8 71 a2 10 00 31 ff 89
RSP: 0018:ffffc90000007d38 EFLAGS: 00000047
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8179ebc2
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8e9a08e8
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1d3411e
R10: 0000000000000000 R11: dffffc0000000001 R12: 1bc16d674eda943a
R13: ffff8880b8e2a5c0 R14: ffff8880b8e2a4c0 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffef782f08 CR3: 000000006086b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __run_hrtimer kernel/time/hrtimer.c:1657 [inline]
 __hrtimer_run_queues+0x334/0xe50 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:preempt_count_add+0x30/0x180 kernel/sched/core.c:5702
Code: fb 48 c7 c0 60 81 33 97 48 c1 e8 03 49 bf 00 00 00 00 00 fc ff df 42 0f b6 04 38 84 c0 0f 85 e2 00 00 00 83 3d 30 03 d5 15 00 <75> 07 65 8b 05 0f f1 a3 7e 65 01 1d 08 f1 a3 7e 48 c7 c0 60 81 33
RSP: 0018:ffffc9000462fad0 EFLAGS: 00000246
RAX: 0000000000000004 RBX: 0000000000000001 RCX: ffffffff97338103
RDX: 000000000000003b RSI: ffffffff8b5d77e0 RDI: 0000000000000001
RBP: 000000000000153a R08: ffffffff8438e904 R09: fffffbfff1d3411e
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff1d3415f
R13: 0000000000003061 R14: 0000000000002af9 R15: dffffc0000000000
 delay_tsc+0x62/0xd0 arch/x86/lib/delay.c:79
 try_check_zero+0x3ee/0x410 kernel/rcu/srcutree.c:975
 srcu_advance_state kernel/rcu/srcutree.c:1549 [inline]
 process_srcu+0x1dc/0x1300 kernel/rcu/srcutree.c:1651
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: rcu_preempt kthread starved for 10505 jiffies! g15097 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:25624 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 11 Comm: kworker/u4:1 Not tainted 6.1.117-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0x1fae/0x3460 kernel/smp.c:998
Code: 2f 44 89 ee 83 e6 01 31 ff e8 ae 43 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 0a e8 39 40 0b 00 e9 1b ff ff ff f3 90 <42> 0f b6 04 2b 84 c0 75 14 41 f7 07 01 00 00 00 0f 84 fe fe ff ff
RSP: 0018:ffffc900001075a0 EFLAGS: 00000293
RAX: ffffffff817f4bd9 RBX: 1ffff110171c8595 RCX: ffff888017f53b80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000107980 R08: ffffffff817f4ba2 R09: fffffbfff224624d
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8e42ca8
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff904e4e010 CR3: 000000000d08e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1334 [inline]
 text_poke_bp_batch+0x2bb/0x940 arch/x86/kernel/alternative.c:1534
 text_poke_flush arch/x86/kernel/alternative.c:1725 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1732
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x12e/0x250 kernel/jump_label.c:207
 static_key_enable+0x16/0x20 kernel/jump_label.c:220
 toggle_allocation_gate+0xbf/0x480 mm/kfence/core.c:804
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/15 21:00 linux-6.1.y 59d7b1a7104a cfe3a04a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in try_check_zero
* Struck through repros no longer work on HEAD.